The Health Effects of Marijuana

Acute effects of THC can be severe but are usually short-lived and temporary. Current literature documents THC s temporary effect on health, suggesting that once the use of marijuana ceases, a rapid recovery from the drug s effects typically occurs. 

However, equating temporary with benign (harmless) would be misleading because some of marijuana s so-called temporary effects can last a lifetime. For example, studies have shown that driving while high can increase the possibility of a motor vehicle accident. In this case, the consequences of marijuana s short-term effects (impaired attention, motor skills, and reaction times) might quickly transform temporary to permanent.  

Chronic effects are frequent, habitual, and long-term. Investigators are also very interested in the chronic health effects of marijuana and THC and their influence on the lives of teenagers. The scientific literature discusses health effects of marijuana on bodily systems. 

How do you define health Many would say health is more than just the absence of disease rather, a healthy person tends to be happy and vital, feeling physically and mentally centered and balanced. The immune system is the body s foundation for feeling healthy. It plays a critical role in protecting the body from illness. It even has a backup system so that if one part of our immunity is compromised, another mechanism is ready to participate in the body s protection and wellness. 

Much research has focused on marijuana s effects on the immune system. Some research has shown that one type of immune system cell called the macrophage (scavenger cell) is particularly sensitive to THC exposure. Macrophages clear the body of viruses, bacteria, and particles that are inhaled or ingested. These studies found the presence of cannabinoid receptors on macrophages, suggesting that THC can disrupt normal immune system functions and may eventually inhibit the body s natural immune response. 

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Smiley, A. (1999). Marijuana On Road and Driving Simulator Studies. In The Health Effects of Cannabis (H. Kalant, W. A. Corrgall, W. Hall and R. G. Smart, eds.). Centre for Addiction and Mental Health, Toronto, Ontario M5S 2S1, Canada. 

The clinical significance of these changes, if any, is still obscure. There are some data suggesting that subjects with diseases with impaired cell-mediated immunity, such as cancer, acute viral infections and uraemia are likely to have lower active T-ceH rosettes, and the active rosette test may be particularly sensitive in this respect. Only long-term studies of the health record of marijuana users as compared with valid controls are ever likely to elucidate the ultimate effects of those changes, if any. 

Consequences of the short-term effects of marijuana can greatly influence a teen s future life. Short-term acute effects describe a condition that is temporary and short-lived longterm chronic effects are cumulative and can last a lifetime. Many studies document the acute and chronic health consequences of smoking marijuana. For instance, there are consistent reports that marijuana temporarily impairs short-term memory and learning. This is confirmed by users of marijuana outside the... 

While the effects of marijuana on health are still being debated, a number of facts seem clear. The effects of marijuana differ from individual to individual. Regularly observed physical effects include a substantial increase in the heart rate, bloodshot eyes, dry mouth and throat, and increased appetite. Short-term memory is reduced, but ideas flow rapidly and the smoker may feel high or hilarious. The most common response is a calm, mildly euphoric state in which time seems to slow down. A song on a compact disc that lasts about two minutes may seem to take twenty minutes. Sensitivity to touch, sights, and sound are enhanced, so the words of the song that once seemed jumbled are now clear—or at least, they seem clear. 

The behavioral effects of prenatal cocaine exposure at age 5 years have been studied in 140 children exposed to cocaine, 61 exposed to alcohol, tobacco, and/or marijuana, and 120 not exposed to any drugs (290). They were evaluated with the Achenbach Child Behavior Checklist. There was no association between behavior and intrauterine cocaine exposure. However, the current behavioral health of the mother, including recent drug use and psychological functioning, did affect the child s internalizing and externalizing behavior. 

Clearly, there is much more work to be done before the precise health and psychological effects of marijuana use are well understood. In fact, many of these health issues remain the subject of much debate. Undoubtedly, opinions on its risks are polarized along the lines of proponents views on what its legal status should be. This polarization of opinion has prevented the development of any consensus on what health information the medical profession should give to patients who are users or potential users of marijuana. There is conflicting evidence about many of the effects of marijuana use. Readers are referred to an excellent article that attempts to summarize in a dispassionate way the evidence on the most probable adverse health and psychological consequences of acute and chronic use of marijuana. ... 

Despite society s focus on the marijuana high, cannabis historically has provided many meaningful industrial and medicinal values that are not attributed to its psychoactive effects. Researchers discovered that cannabis crops farmed as far back as 12,000 years ago yielded hemp, a distinct variety of the cannabis plant associated with little or no psychoactivity. The first evidence of the medicinal use of cannabis can be traced to a Chinese health publication from... 

Studies indicate that both the acute and chronic effects from smoking marijuana often mirror the short-term and long-term effects associated with smoking tobacco. Smoke is made up of both solid and gas particles. The inhalation of hot gases combined with volatile tars (and other particulates) can be very harmful to the lungs, throat, and bronchial tubes. Short-term health effects from smoking marijuana can... 

Eating or smoking marijuana has been shown to increase heart rate by 20 to 50 percent. This effect can occur within a few minutes to a quarter of an hour and can last for up to three hours. Because of the brain s tolerance to THC, it has been shown that these effects are temporary. However, marijuana users who do not know about or expect these acute health effects may find them unpleasant or even scary, resulting in panic or anxiety reactions. And, those with heart problems or other physical disorders may have disturbing or even harmful effects as a result of cannabis use. 

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